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Interview · Technical

Backend engineer

Covers data modelling, API design, concurrency, caching, failure handling and running a service in production, all answered in words. Suits mid-level and senior backend engineers. Follow-ups push past the first idea to the failure case, the trade-off and how the candidate would know it worked.

Suits: Backend engineer, Software engineer, API developer, Platform engineer

Questions
7 of 17
Length
35 min
Format
Voice or typed
Levels
Mid to Senior
See this interview on a 30-minute call.
AI interviewerScored
Example

  1. Interviewer: Tell me about a time you changed someone's mind at work. How did you go about it?

  2. Candidate: Our team wanted to rebuild the billing page from scratch, and I thought it was the wrong call, so we put together a plan to…

  3. Follow-up

    Interviewer: You said "we". What did you say yourself, and what finally changed their mind?

  4. Scored on

    • Data and API design30%
    • Correctness under failure30%
    • Debugging and operations25%
    • Trade-off communication15%

    Score, reasons and recording. Your team decides.

An example exchange. This interview's own questions open when you use it.

What it listens for, and how much each part counts.

Every answer is scored against this guide, with the reasoning written beside the score. You get the recording or the written answers too, and your team makes the call.

  • Data and API design30%
    Models data and shapes APIs around real access patterns and change.
  • Correctness under failure30%
    Handles races, retries and partial failure so data stays right.
  • Debugging and operations25%
    Finds causes from evidence and builds services others can run.
  • Trade-off communication15%
    Explains costs and choices plainly to engineers and non-engineers.

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